So-called "strapdown references" do not require the complicated servo mechanics of gimballed references suspended in a frame that previous devices required. See DE-OS No. 32 33 029. However, as the sensors required by a three axes strapdown reference instrument (roll axis, 1st and 2nd transverse axis) are costly and complex, such instruments are too expensive for general use.
In particular, as the roll axis measurement requires a relatively high measurement range and high scaling fidelity, a sensor which uses the Sagnac effect is preferred to other sensor types, particularly if great precision is required. Such Sagnac effect sensors can be formed using a ring laser sensor, an optic fiber sensor, or a micro-optic resonator laser sensor. Unfortunately, for a complete three-axis reference such sensors are also too expensive and complex for general use. Therefore, in light of the present state of the art, there exists a need for a sufficiently accurate and simple angular velocity sensor for the application in strapdown references.